True, these symptoms are all quite normal in a person experiencing this serious mental illness.

They are also hallmarks of ADD/ADHD.

Bipolar disorder and ADD/ADHD (Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder) share many overlapping symptoms and are also quite frequently found to co-exist in one patient.

Between five and 20 per cent of individuals with bipolar disorder also experience ADD/ADHD.

Because of their overlapping symptoms and frequent comorbidity, it can sometimes be difficult to properly diagnose these conditions or to correctly identify when both are present in the same individual.

A recent study published in the journal Bipolar Disorders has discovered that brain structure abnormalities previously thought to be linked solely to bipolar disorder may actually be specific to both conditions occurring together.

In this MRI study, scientists from the University of California attempted to determine how ADD/ADHD and bipolar disorder each contribute to brain structure abnormalities.

They scanned four groups of patients. Some had only bipolar disorder, some had only ADD/ADHD, some had both conditions and one group had no mental illness.

Using MRI, they measured cortical thickness in each group and found that overall cortical thickness was less in those with bipolar disorder regardless of their ADD/ADHD status.

Interestingly, in two areas of the brain the effect of bipolar disorder on the cortical thickness was different in those with and without ADHD.

In the right orbitofrontal cortex and the left subgenual cingulate, cortical thinning was less or non-existent for those with comorbid ADD/ADHD. This finding shows us a unique connection between the two conditions at the level of brain structure.

It will likely prove useful as we move forward to further understanding of these two conditions and how they interact.

Until we have definitive diagnostic testing for these conditions, we do have some ways to distinguish between bipolar disorder and ADD/ADHD today.

First, we can examine the age of onset. ADD/ADHD is present right from early childhood whereas bipolar disorder typically presents after puberty. Consistency of symptoms is also a clue.

In ADD/ADHD, symptoms are always present. Bipolar disorder symptoms come and go in an episodic way.

We can also examine the triggers, rapidity and duration of mood shifts.

In ADD/ADHD, mood shifts are usually clearly triggered by life events, they can change very quickly throughout a day depending on what is happening and moods tend not to last nearly as long as the mood states commonly found in bipolar disorder.

If you think you or a loved one may have one or both of these conditions, there is good help available. Speak to a mental health professional to get an accurate diagnosis and learn about options for managing these conditions.

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